1. Field of the Invention
The present invention relates to a video camera. More specifically, the present invention relates to a compact video camera with electronic picture stabilizer, which is utilized as a camcorder, for example.
2. Description of the Related Art
One example of a method for detecting an unintentional motion component of an image sensing device is disclosed in, for example, the 20th image engineering conference in 1989 by Matsushita Electric Industrial Corporation. In this prior art method, by utilizing a motion vector obtained by a representative point matching method disclosed in, for example, Japanese Patent Application Laying-open No. 61(1986)-201581 H04N 7/137!, the motion component of the image sensing device is detected according to image information. In this prior art, an attenuation coefficient is used for performing the correction of a blurring of an image due to the unintentional motion, i.e. the electronic picture stabilization. Furthermore, four detection areas are arranged in an image field or screen, and therefore, four portion motion vectors are obtained from the image field.
Now, a method for performing the correction of the blurring of the image due to the unintentional motion, i.e., the electronic picture stabilization on the basis of the portion motion vectors will be described. As a whole motion vector, a mean value of the four portion motion vectors, or a mean value of two portion motion vectors having intermediate values in the four portion motion vectors is utilized. If the whole motion vector is V.sub.n, an integration vector S.sub.n is represented by the following equation. EQU S.sub.n =k.multidot.S.sub.n-1 +V.sub.n
where, k is called as an attenuation coefficient, being a decimal number smaller than 1.
As shown in FIG. 9, for example, an image extracting position is moved by utilizing the integration vector S.sub.n thus obtained, whereby a blurring of an image due to the unintentional motion of the video camera is corrected.
However, in this prior art method, even if the whole motion vector V.sub.n is zero, the image extracting position is centered such that the integration vector S.sub.n approaches zero with time lapse. That is, there was a problem in the prior art method that the image in the screen moves even when no movement occurs in the video camera.